iOS小结
- 1、相应点击指定view区域
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
NSSet *allTouches = [event allTouches]; //返回与当前接收者有关的所有的触摸对象
UITouch *touch = [allTouches anyObject]; //视图中的所有对象
CGPoint point = [touch locationInView:self.view]; //返回触摸点在视图中的当前坐标
int x = point.x;
int y = point.y;
NSLog(@"touch (x, y) is (%d, %d)", x, y);
}
- 2、修改UITextField的默认颜色文字大小
修改默认颜色
self.textField.placeholder = placeholder;
[self.textField setValue:[UIColor colorwithHexString:@"cccccc"] forKeyPath:@"_placeholderLabel.textColor"];
[self.textField setValue:[UIFont boldSystemFontOfSize:14] forKeyPath:@"_placeholderLabel.font"];
- 3、去掉字符串的空格
NSString *str = @" sdsdijls ijdlsj sdffsd;kl fs;dkf;s";
//去掉开头和结尾的空格
NSString *str1 = [str stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
//替换的方法 。去掉所有空格
NSString *str2 = [str stringByReplacingOccurrencesOfString:@" " withString:@""];
str1 = @"sdsdijls ijdlsj sdffsd;kl fs;dkf;s";
str2 = @"sdsdijlsijdlsjsdffsd;klfs;dkf;s";
- 4、修改UITextField文字贴在边框的
// 默认情况下,当向textField输入文字时,文字会紧贴在textField左边框上.我们可以通过设置textField的leftView,设置一个只有宽度的leftView.这样还不够,因为默认leftView是不显示的.还需要将leftViewMode设置为UITextFieldViewModeAlways.这样就完成了.
//设置文本框左边的view
UITextField *textField = [[UITextField alloc]init];
textField.frame = CGRectMake(10, 30, 300, 30);
[self.view addSubview:textField];
textField.leftView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 8, 0)];
//设置显示模式为永远显示(默认不显示)
textField.leftViewMode = UITextFieldViewModeAlways;
- 5、取数组中n个元素
取数组中n个元素
NSArray *array = @[@"品牌",@"颜色",@"上牌时间",@"行驶里程",@"描述"];
NSArray * array1 = [array objectsAtIndexes:[NSIndexSet indexSetWithIndexesInRange:NSMakeRange(1, 3)]];
NSLog(@"array1==%@",array1);
- 6、在UITableView上添加tap手势可用的方法:
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapCounts)];
tap.cancelsTouchesInView = false;
[tableView addGestureRecognizer:tap];
- 7、UITableviewCell上的控件在点击cell时候背景颜色消失的解决方案：
lable.layer.backgroundColor=[UIColor redColor].CGColor;
- 8、打包上传app时候报错和对应的解决方法
1、ERROR ITMS-90049: “This bundle is invalid. The bundle identifier contains disallowed characters. [See the section of the Application Programming Guide entitled The Application Bundle.]”
解决方案：找到第三方库中得info.plist文件添加bundle id ，修改bundle version ，bundle version string
具体解决步骤：在xcode左下角搜索框搜索info.plist，搜索出所有info.plist文件对这三个key缺少的添加，不对的修改
2、
ERROR ITMS-90530: “Invalid MinimumOSVersion. Apps that only support 64-bit devices must specify a deployment target of 8.0 or later. MinimumOSVersion in ‘dqcclient.app’ is ‘7.0’.”
解决方案：编译时拔掉真机，否者编译会针对真机的系统架构进行编译
3、
ERROR ITMS-90535: “Unexpected CFBundleExecutable Key. The bundle at ‘dqcclient.app/TencentOpenApi_IOS_Bundle.bundle’ does not contain a bundle executable. If this bundle intentionally does not contain an executable, consider removing the CFBundleExecutable key from its Info.plist and using a CFBundlePackageType of BNDL. If this bundle is part of a third-party framework, consider contacting the developer of the framework for an update to address this issue.”
解决方案：在xcode左下角搜索框搜索info.plist，搜索出所有info.plist文件，删除掉第三方info.plist文件中的Executable file 字段
4、
ERROR ITMS-90529: “Invalid package. Applications built with sdk 9.0 or later must be packaged as proper IPA files.”
解决方案：现在上传需是IPA文件
具体解决步骤：将xcode编译的.app文件放入Payload文件夹内，压缩成.zip文件，修改其后缀为.ipa文件，即可。
- 9、UITableViewCell 上的imageView 用SDWebimage 加载图片时候 出现内存暴涨的现象：
1.同时加载图片过多；
2.加载的图片过大；
- 10、添加延时方法 和取消延时的方法
[self performSelector:@selector(hidden) withObject:self afterDelay:3];
[NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(hidden) object:nil];//取消对应的方法
[NSObject cancelPreviousPerformRequestsWithTarget:self];//取消全部。
[[self class] cancelPreviousPerformRequestsWithTarget:self];//取消全部。
- 11、判断数组中存在某个元素
NSArray *array = @[@"品牌",@"颜色",@"上牌时间",@"行驶里程",@"描述"];
//判断数组中存在某个元素
if ([array indexOfObject:@"品牌"]!= NSNotFound) {
NSLog(@"存在");
}
- 12、xib上拖ScrollView 添加约束后再加label、button等导致scrollView无法滑动
-(void)viewDidAppear:(BOOL)animated{
[super viewDidAppear:animated];
self.scrollView.frame = CGRectMake(0, 0, kScreenWidth, kScreenHeight);
[self.scrollView setContentSize:CGSizeMake(kScreenWidth, 1000)];
}
- 13、数学公式
NSLog(@"%i",abs(-3));
NSLog(@"%d",abs(-4));
//floor() 向下取整
NSLog(@"%f",floorf(-3.1415926));
NSLog(@"%d",(int)floorf(-3.1415926));
// ceil()向上取整
NSLog(@"%f",ceilf(3.14));
NSLog(@"%d",(int)ceilf(3.14));
//round() 四舍五入
NSLog(@"round()%f",roundf(3.14));
NSLog(@"round()%d",(int)roundf(3.14));
NSLog(@"round()%f",roundf(3.74));
//fmax()求两个数的最大值
NSLog(@"fmax()%f",fmaxf(3.14, 2.71));
NSLog(@"fmax()%d",(int)fmaxf(3.14, 2.71));
//------------------- 可以嵌套
NSLog(@"fmax()%f",fmaxf(20.69, fmaxf(3.14, 19.87)));
//fmin()求两个数的最小值
NSLog(@"fmin%f",fmin(14, 12));
NSLog(@"fminf()%d",(int)fminf(3.14, 3.141));
//fmod()求两个数整除后的余数
NSLog(@"fmodf%f",fmodf(5.00, 3.00));
//modf()/modff()/modfl() 浮点数分解为整数和小数
float a;
float c;
float b = 8.22;
a = modff(b, &c);
NSLog(@"modf()-整数部分-%f",c);
NSLog(@"modf()-小数部分-%f",a);
打印结果:
打印结果：
2015-08-13 14:09:55.520 Micro Shop[15342:164204] 3
2015-08-13 14:09:55.564 Micro Shop[15342:164204] 4
2015-08-13 14:09:55.565 Micro Shop[15342:164204] -4.000000
2015-08-13 14:09:55.565 Micro Shop[15342:164204] -4
2015-08-13 14:09:55.565 Micro Shop[15342:164204] 4.000000
2015-08-13 14:09:55.565 Micro Shop[15342:164204] 4
2015-08-13 14:09:55.565 Micro Shop[15342:164204] round()3.000000
2015-08-13 14:09:55.565 Micro Shop[15342:164204] round()3
2015-08-13 14:09:55.565 Micro Shop[15342:164204] round()4.000000
2015-08-13 14:09:55.566 Micro Shop[15342:164204] fmax()3.140000
2015-08-13 14:09:55.566 Micro Shop[15342:164204] fmax()3
2015-08-13 14:09:55.566 Micro Shop[15342:164204] fmax()20.690001
2015-08-13 14:09:55.566 Micro Shop[15342:164204] fmin12.000000
2015-08-13 14:09:55.566 Micro Shop[15342:164204] fminf()3
2015-08-13 14:09:55.566 Micro Shop[15342:164204] fmodf2.000000
2015-08-13 14:09:55.566 Micro Shop[15342:164204] modf()-整数部分-8.000000
2015-08-13 14:09:55.567 Micro Shop[15342:164204] modf()-小数部分-0.220000
- 14、label增加留白（重写 - (CGSize)intrinsicContentSize）
- (CGSize)intrinsicContentSize {
CGSize originalSize = [super intrinsicContentSize];CGSize size = CGSizeMake(originalSize.width+20, originalSiz
e.height+20);return size;
}
如果是用代码约束，如果你只想设置坐标不想设置大小，那么你需要像上面的代码一样，在- (CGSize)intrinsicContentSize为你的label指定一个默认大小
如果是在Xib里，那么你需要在下面这个Instrinsic Size的属性里设置为placeholder，这样，Xcode就不会报错了
